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Help please please please

Help please please please-example-1

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Answer:

1.
F_1(0,-√(35)),\ F_2(0,√(35)).

2.
F_1(0,-√(12)),\ F_2(0,√(12)).

3.
F_1(-√(5),0),\ F_2(√(5),0).

Explanation:

The foci of ellipse have the coordinates
F_1(-c,0),\ F_2(c,0), where
c=√(a^2-b^2) if a>b and
F_1(0,-c),\ F_2(0,c), where
c=√(b^2-a^2) if b>a.

1.
a=1,\\ \\b=6,\\ \\c=√(36-1)=√(35)

and foci are on y-axis
F_1(0,-√(35)),\ F_2(0,√(35)).

2.
a=2,\\ \\b=4,\\ \\c=√(16-4)=√(12)

and foci are on y-axis
F_1(0,-√(12)),\ F_2(0,√(12)).

3.
a=3,\\ \\b=2,\\ \\c=√(9-4)=√(5)

and foci are on x-axis
F_1(-√(5),0),\ F_2(√(5),0).

Help please please please-example-1
User Praveen Ojha
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